Lower levels of vitamin C in plasma and urine of Japanese male smokers.

We studied the vitamin C status of smokers and nonsmokers among staff members of our university in 1982. This paper describes the results from the 1983-85 studies. Plasma vitamin C levels (M +/- SD, mg/dl) from smokers and nonsmokers, respectively, were as follows: 0.49 +/- 0.15 (n = 51) and 0.72 +/- 0.23 (n = 73) in 1983, 0.56 +/- 0.13 (n = 48) and 0.84 +/- 0.21 (n = 88) in 1984, and 0.52 +/- 0.15 (n = 56) and 0.86 +/- 0.24 (n = 93) in 1985. The differences between smokers and nonsmokers are all highly significant. Urinary vitamin C levels (M +/- SD, mg/dl) from smokers and nonsmokers, respectively, were 1.8 +/- 0.6 and 2.6 +/- 0.9 in 1983 and 2.0 +/- 0.7 and 2.9 +/- 1.0 in 1984. These differences between the two groups are also highly significant. Both groups were similar in age, height, weight, general health parameters, and vegetable and fruit consumption. Plasma and urinary vitamin C levels were significantly higher in smokers taking vitamin C supplement than in those not taking vitamin C supplement.